powerpc: make iSeries boot

Now that we use the device tree, it helps to build it in.
It helps to links the kernel at the correct address.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

arch/powerpc/Kconfig

@@ -317,7 +317,7 @@ config PPC_BPA
 
 config PPC_OF
 	bool
-	depends on PPC_MULTIPLATFORM	# for now
+	depends on PPC_MULTIPLATFORM || PPC_ISERIES
 	default y
 
 config XICS
@@ -836,7 +836,7 @@ endmenu
 if PPC64
 config KERNEL_START
 	hex
-	default "0xc0000000"
+	default "0xc000000000000000"
 endif
 
 source "net/Kconfig"

arch/powerpc/Kconfig.debug

@@ -55,7 +55,7 @@ config BDI_SWITCH
 
 config BOOTX_TEXT
 	bool "Support for early boot text console (BootX or OpenFirmware only)"
-	depends PPC_OF
+	depends PPC_OF && !PPC_ISERIES
 	help
 	  Say Y here to see progress messages from the boot firmware in text
 	  mode. Requires either BootX or Open Firmware.